Gravel bikes have been experiencing a renaissance over the past several years.
It wasn’t that long ago that most serious riders would scoff at throwing chunky tires on a gravel frame to get more versatility, as a good hardtail mountain bike could likely do the same thing, only better.
Naturally, a full-suspension gravel bike may seem like a stretch for some. But as gravel riding matures, so too have the rigs available for the weird in-between spaces.
Cannondale’s latest full-suspension Topstone Carbon Lefty gravel line marks a significant step into that sort of specialization, simultaneously striving to be a bike that is as efficient on the road as it is compliant in the rough.
The Cannondale Topstone has been the brand’s key gravel rig for years. But the latest version features a sharp carbon frame and trail-smoothing front and rear suspension, making the Topstone among the most comfortable gravel bikes.
After spending 2 days on the Topstone Carbon 2 Lefty in the Colorado mountains, I feel like Cannondale has come up with something that isn’t exaggerating when it says “nothing is impassable.”
Topstone Carbon 2 Lefty
Cannondale’s Topstone Carbon 2 Lefty isn’t the most expensive option in the Topstone lineup, but it is about the closest thing to a mountain bike as you’ll find in a drop-bar gravel bike. However, this is decidedly not a mountain bike or a road bike for that matter.
It is a special kind of platform that felt like it reached up to fill gaps between road and dirt, rather than making compromises. It never really strayed too far toward the feel of a road or mountain bike to make it anything other than a dedicated gravel rig.
I spent 2 days putting more than 70 miles on the Carbon 2 Lefty on a mix of road, gravel, and singletrack in Aspen, Colorado. I made sure to punish my body to the best of my ability to see how the bike held up.
Those 70 miles came with nearly 3,000 feet of elevation each day on varied terrain. I got a good feel for how the bike functions in a wide variety of conditions. For a rider based in Austin, Texas, that kind of elevation is something I always have to travel for, and it is always punishing on my body.
The Topstone proved to be the companion I needed to reduce some of the fatigue that would usually cut my time in the saddle short at higher elevations.
Descending, the bike was fast, fun, and snappy. Cannondale’s Kingpin rear suspension helped the bike hook up to dirt and rocks to prevent sliding out. Likewise, the Lefty Oliver Fork made big impacts feel less severe.
The suspension setup created more handling compliance while reducing the fatigue many gravel riders feel building in their arms, hands, and backs during big rides.
I frequently found myself seeking out kickers to spring myself off of. I felt comfortable in the knowledge that my wrists wouldn’t buckle from a front-heavy landing thanks to the Lefty. The rear wheel felt glued to the ground, so coming into corners hot wasn’t as problematic as on rigid bikes.
The rear suspension provides 30 mm of travel at the saddle. You get an additional 10 mm or so of rear axle travel due to rear triangle frame flex.
The Lefty fork delivers 30 mm of travel. It isn’t much, but it created just enough flex to feel responsive and playful while retaining efficiency on climbs and sprints when conditions called for it.
The Carbon 2 Lefty also features a dropper post, which is one of those features that seems to scream “off-road” at the top of its lungs. It gave the bike an even greater feeling of capability, especially while pointed downhill.
The bike still felt like a comfortable climber. It didn’t bob under force, and the same flex that helped it track well in furious descents kept me from getting bumped out of the saddle while creeping over roots and rocks on steep-graded singletrack.
Taken alone, the Kingpin, dropper, or Lefty Oliver fork would all be welcome additions to my rigid gravel bike. Taken together, they are more of a revelation. Despite my lungs and legs burning, I was remarkably comfortable over every type of terrain.
The Topstone Carbon line is available in rigid and suspension fork options, but all feature Cannondale’s Kingpin suspension system.
With the Kingpin setup, the back of the Topstone frame flexes around a through-axle pivot positioned on the seat tube to create an integrated rear suspension that doesn’t require a shock. Because it functions through flexing, it doesn’t have a true bottom-out mark and doesn’t require servicing like other suspension systems.
It’s a bit counterintuitive. Carbon usually is lauded for its stiffness, which gives riders more efficiency through the transfer of power through the frame. Cannondale has instead used carbon as a pliable material to increase comfort and compliance, not rigidity.
While riding behind a Topstone Carbon, I saw the flex of the bike, but it’s not something I felt while riding in the same way as a traditional air or coil shock. The flex was subtle enough that I forgot about it until I realized that the terrain should have felt tougher, or I took a big enough hit to recognize it.
Kingpin made a particularly impressive difference when descending in widely varying conditions or while peddling over chunky gravel or single track. The movement of the frame’s rear helped the bike’s tires track the ground consistently. That feeling contributed to less time spent chattering into corners or drifting.
The Carbon 2 Lefty’s dropper post made the bike feel like an ultra-stable platform while descending, even at speeds of 40 mph or more. The low center of gravity the bike afforded me was confidence-inspiring no matter the terrain.
Using the dropper post slightly inhibited the bike’s amount of travel, as the Kingpin is meant to flex all the way up to the rider through the seat post. But the motion makes a big difference with either setup.
The bike has enough space for 700c x 45mm tires or 650b tires up to 2.1 inches. But the extra help from the front and rear suspension gives similar levels of compliance with smaller, faster, and lighter tires. Most rigid bikes could only find that with bigger options.
The Lefty Oliver gravel fork brought 30 mm of travel to the front of the bike, turning light gravel into butter. And it significantly smoothed out more technical terrain, including rough gravel roads and singletrack trails peppered with rocks and roots.
Even large potholes on the road that would send riders over the bars in a heartbeat felt like small bumps. The Lefty Oliver’s progressive tuning only kicked in when the bike took a big enough hit to generate a response. Often, especially while climbing, I wasn’t aware that the shock was doing anything at all.
I didn’t feel large, springy movements or dramatic flexes that seemed like power dumps unless I put my body’s full weight into the bars. For those times when I fully loaded the front, the fork features a full lockout option that stiffened things up.
While riding the Topstone Carbon 2 Lefty, I was surrounded by others riding the rigid-fork sibling, the Topstone Carbon 1 RLE. The significant differences between these two bikes are the Carbon 1 RLE’s rigid fork and its included SmartSense system.
Cannondale says it doesn’t include SmartSense in the Topstone Carbon Lefty models to keep the price down, which is understandable. It’s already giving riders a full-suspension, carbon gravel bike with a fork that costs more than an MSRP of $1,500. Throwing SmartSense on could price out a large contingent of buyers.
However, the Carbon 2 Lefty is built to accept the system, should riders opt to spring for the additional cash, as are all Topstone Carbon models.
SmartSense is a fully integrated radar and light system that includes the Garmin Varia Radar, Lezyne front and rear lights, and a Cannondale wheel sensor. A single battery that mounts to the frame powers the whole system. It starts automatically when the bike moves and uses light and sound alerts to ensure that riders are aware of approaching traffic and vice versa.
Riders can customize and control the system through Cannondale’s app. Only the higher-end models of the rigid-fork Topstone Carbon come equipped with SmartSense. Without the system installed, the battery mount in the frame functions as a spare tube or tool storage area.
Who Is the Cannondale Carbon 2 Lefty For?
The Topstone Carbon Lefty is a bike that begged for chunky, aggressive gravel riding. The Lefty Oliver provided comfort to the arms and upper body, significantly reducing fatigue after hours of rattling over challenging terrain.
The rigid fork Topstone Carbon lineup is more efficient and includes SmartSense technology to make time on the road safer. It also has more mount points for gear for bikepackers and those who need to haul more equipment.
Both are comfy and capable bikes that make gravel riding more fun and accessible.
Cannondale Topstone Builds and Pricing
In a word, Cannondale’s Topstone Carbon lineup is all about versatility, both in features and price points.
The Topstone Carbon Lefty models come in four varieties. The Topstone Carbon Lefty 1 and Carbon 1 Lefty, go for MSRP of $8,500 and $7,850, respectively. The Carbon Lefty 1 is pricier and features the SRAM Force X01 Eagle eTap AXS mountain bike groupset. The Carbon 1 Lefty trades that out for the SRAM Force eTap electronic 12-speed road groupset.
The Topstone Carbon 2 Lefty and Carbon 3 Lefty cost an MSRP of $4,250. The Carbon 2 Lefty comes with a Shimano GRX800 11-speed groupset. The Carbon 3 Lefty features the Shimano GRX 11-speed groupset.
The only bike in the bunch that comes with a dropper post is the Carbon 2 Lefty.
Topstone Carbon Models without the Lefty fork range from an MSRP of $7,850 for the Topstone Carbon 1 RLE to $2,625 for the Carbon 6.
The Carbon 1 RLE features all of the bells and whistles of the platform. It includes the integrated SmartSense system and the SRAM Force eTap electronic 12-speed groupset. The Carbon 6 drops SmartSense and includes the Shimano GRX 400 10-speed groupset. Multiple builds exist for riders to find the ideal setup to meet their performance and price point.
Either way, the Cannondale Topstone Carbon lineup will make your gravel grinds much less of a grind.